Large-height-diameter-ratio titanium-aluminum alloy blank manufacturing device and method

Abstract

The invention provides a large-height-diameter-ratio titanium-aluminum alloy blank manufacturing device and method. The method comprises the following steps that S10, a blank is designed, specifically, a forge piece is designed according to a target titanium-aluminum alloy blade; the forge piece comprises a blade root part, a blade body part and a blade crown part; presetting the shape size of the blank according to the forge piece; s20, a forming die and raw materials are obtained, specifically, the forming die is prepared according to the preset shape and size of the blank in the step S10, and a bar is selected; s30, the bar is subjected to upsetting forming through the forming die, and a blank is obtained; and carrying out hot working on the blank to obtain the target titanium-aluminum alloy blade forge piece. According to the large-height-diameter-ratio titanium-aluminum alloy blank making method and device, the problems that large-height-diameter-ratio metal bar blank making is unstable and the die cost is high due to titanium-aluminum alloy isothermal forming can be solved, non-isothermal forming of large-height-diameter-ratio titanium-aluminum alloy special-shaped piece blank making is achieved, the material utilization rate is increased, waste of titanium-aluminum alloy materials is reduced, and the large-height-diameter-ratio titanium-aluminum alloy blank making method and device are suitable for large-height-diameter-ratio titanium-aluminum alloy blank making. And the machining cost of the blade is effectively reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of accessory preparation in high-end manufacturing equipment industry, and in particular to a device and method for making a titanium-aluminum alloy billet with a large aspect ratio. Background Art

[0002] As a new type of high-strength, lightweight and high-temperature resistant material, titanium aluminum alloy has shown great application potential in the manufacture of high-temperature components such as aerospace engines due to its excellent specific strength and excellent high-temperature performance. It can partially or completely replace traditional high-density nickel-based and iron-based materials and is widely used in aerospace engine turbine blades and high-performance automotive engine turbocharger impellers.

[0003] However, the inherent brittleness of titanium aluminum alloys poses significant challenges to their hot working. This material is prone to cracks and fractures during conventional hot working, which greatly limits the application of traditional hot working technology. In order to overcome the brittleness of the material and achieve plastic deformation, titanium aluminum alloys usually need to be isothermally formed at extremely high temperatures, generally in the range of 1000-1400°C. This high temperature environment places stringent requirements on mold materials. Ordinary mold steels cannot withstand such high temperatures, so expensive nickel-based high-temperature alloys and molybdenum-based alloys are often used as mold materials, which further increases processing costs.

[0004] For parts with complex geometries, such as Figure 1 The engine blade shown in the figure has a thinner and longer blade body with a smaller cross-sectional area, while the blade crown and blade root are thicker and shorter with a larger cross-sectional area. This structural characteristic results in the required blank being a dumbbell-shaped part with larger ends and a smaller middle (such as Figure 2 As shown in the figure, and the height-to-diameter ratio of the blank is greater than 4, it is very easy to cause instability during the forming process. At present, the common practice is to directly machine or machine the metal bars of equal diameter into a specific shape and then forge them. This method not only leads to low material utilization, but also greatly increases the cost of machining due to the complex post-processing process.

[0005] In addition, although the high temperature isothermal forming process solves the problem of material brittleness, the high temperature conditions have extremely high requirements for equipment and molds, and the use of expensive high temperature alloy materials makes the overall processing cost high. At the same time, due to the special properties of the material, the processing cycle is long, which affects production efficiency.

[0006] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0007] In view of this, the present invention proposes a device and method for making titanium-aluminum alloy billets with a large aspect ratio to solve the problem of instability in the making of metal bars with a large aspect ratio, realize the non-isothermal forming of titanium-aluminum alloy special-shaped parts with a large aspect ratio, improve material utilization, reduce the waste of titanium-aluminum alloy materials, and effectively reduce the machining cost of blades. At the same time, the non-isothermal forming method can avoid the use of a large amount of high-temperature alloys as mold materials, thereby reducing costs.

[0008] The technical solution of the present invention is achieved in this way:

[0009] In a first aspect, the present invention provides a titanium aluminum alloy billet making device with a large aspect ratio, comprising a bar, a forming die, a sleeve ring, a pressure rod, a base heating furnace and a base; the bar is nested in the forming die after lubrication pretreatment; the forming die is nested in the sleeve ring; the bar, the forming die and the sleeve ring form a whole, namely, an upsetting assembly;

[0010] The base heating furnace surrounds and connects the base and the pressure rod, and is used to heat the base and the pressure rod, and the base and the pressure rod are arranged opposite to each other to form a preheating and heat preservation system;

[0011] The upsetting assembly is placed in the base to fix and support the upsetting assembly; the pressure rod is used to apply pressure to the bar material to complete the upsetting process.

[0012] In the present invention, the sleeve ring can be made of a high-temperature alloy having high strength and thermal stability at 1000-1400° C., preferably a nickel-based high-temperature alloy; the base is made of mold steel.

[0013] On the basis of the above technical scheme, preferably, the forming mold adopts a ceramic mold; the collar is selected from nickel-based alloy K403 or nickel-based alloy N403; the pressure rod adopts nickel-based alloy or ceramic material; the base adopts mold steel H13; the outer diameter of the forming mold is 2-3 times the diameter of the rod, and the minimum diameter of the through hole of the forming mold is equivalent to the diameter of the rod.

[0014] On the basis of the above technical solution, preferably, the base is not completely placed in the base heating furnace to facilitate external air cooling and heat dissipation, so that a certain temperature gradient exists in the base, thereby supporting and enhancing the compressive stress of the internal upsetting components.

[0015] On the basis of the above technical solution, preferably, the upsetting component, the pressure rod and the base all need to be heat-insulated; the insulation temperature of the upsetting component is 1000-1400°C, and the time is 30-120min; the insulation temperature of the pressure rod and the base is 500-800°C, and the time is 1-5h.

[0016] In a second aspect, the present invention is directed to a method for making a titanium-aluminum alloy billet with a large aspect ratio based on the above-mentioned device, characterized in that it comprises the following steps:

[0017] S10. Design of blanks:

[0018] Designing a forging according to the target titanium aluminum alloy blade; the forging includes a blade root, a blade body and a blade crown; and presetting the shape and size of the blank according to the forging;

[0019] S20, obtaining a forming die and raw materials: preparing a forming die according to the preset shape and size of the blank in step S10, and selecting a bar material;

[0020] S30, using the forming die to perform upsetting forming on the bar material to obtain a blank;

[0021] The blank is hot worked to obtain a target titanium-aluminum alloy blade forging.

[0022] Based on the above technical solution, preferably, in step S20, the selecting of the bar material includes:

[0023] According to the shape and size of the blank in step S10, a bar with a height-to-diameter ratio greater than 4 is selected as the raw material; the bar includes a first end, a middle portion, and a second end;

[0024] The first end and the second end of the bar are heated, kept warm and upset respectively, and the middle part is not deformed, so as to obtain a blank.

[0025] More preferably, the bar stock needs to be lubricated before upsetting, and the lubricated pretreatment is to coat the bar stock with a glass lubricant; the coating thickness of the glass lubricant is 1-2 mm.

[0026] More preferably, the upsetting speed is 1 to 10 mm / s.

[0027] On the basis of the above technical solution, preferably, in step S30, the upsetting forming adopts a non-isothermal forging method; the upsetting forming temperature is 1000-1400° C.; after the upsetting forming is completed, the height-to-diameter ratio H / D of the forging is less than 2.5.

[0028] On the basis of the above technical solution, preferably, the target titanium aluminum alloy blade is TiAlXZ;

[0029] Wherein, X is at least one of Nb, Mo, Cr, Ta, V, and Mn; Z is at least one of Fe, C, N, O, B, and Si;

[0030] The atomic percentage of Al is 43%-48%, the atomic percentage of X is 0%-8%, and the atomic percentage of Z is 0%-1%.

[0031] In a third aspect, the present invention provides a titanium-aluminum alloy blade produced by the above-mentioned billet making method.

[0032] The device and method for making a titanium-aluminum alloy billet with a large aspect ratio provided by the present invention have the following beneficial effects compared with the prior art:

[0033] 1. In the present invention, high-quality ceramics with high compressive strength at high temperatures are used as forming molds, and a reasonable cavity is designed to reduce the height-to-diameter ratio of the deformed part of the titanium-aluminum alloy to avoid instability; a high-strength high-temperature alloy sleeve ring with thermal stability is used to apply compressive stress to the forming mold to enhance the compressive capacity of the forming mold and avoid cracking and failure of the forming mold; the base is made of mold steel with a relatively low insulation temperature, which can support and enhance the compressive stress of the internal sleeve ring and the mold; and only the forming mold needs to be replaced between several upsetting passes. In addition, the device of the present invention avoids the use of a single high-temperature alloy or ceramic material. In terms of structure, high-quality mold steel is used as the base, a sleeve of ceramic is used as the forming mold, and a high-temperature alloy is selected as the supporting sleeve ring to form a composite structure, which effectively reduces the mold cost.

[0034] 2. The device and method for making titanium-aluminum alloy billets with a large aspect ratio of the present invention can solve the problems of instability in billet making of metal bars with a large aspect ratio and high mold cost caused by isothermal forming of titanium-aluminum alloys, realize non-isothermal forming of titanium-aluminum alloy special-shaped parts with a large aspect ratio, improve material utilization, reduce waste of titanium-aluminum alloy materials, and effectively reduce the machining cost of blades. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 It is a schematic diagram of the titanium aluminum alloy blade special-shaped part mentioned in the background technology;

[0037] Figure 2 It is a schematic diagram of the dumbbell-shaped special-shaped blank mentioned in the background technology;

[0038] Figure 3Schematic diagram of the forming die of the present invention; in the figure, (a) is a schematic diagram of a one-pass upsetting forming die; (b) is a schematic diagram of a two-pass upsetting forming die; 1 is a bar material, 21 is a first set of forming dies; 1' is a one-pass upsetting forming blank, and 22 is a second set of forming dies;

[0039] Figure 4 The schematic diagram of one-pass upsetting of the present invention; in the figure, (a) is the upsetting assembly; (b) is the preheating and heat preservation system; (c) is the upsetting device;

[0040] Figure 5 The schematic diagram of the two-pass upsetting of the present invention; in the figure, (a) is the upsetting assembly; (b) is the preheating and heat preservation system; (c) is the upsetting device;

[0041] Figure 3 to Figure 5 In the figure, 1 is a bar, 2 is a forming die, 3 is a sleeve ring, 4 is a pressure rod, 5 is a base heating furnace, and 6 is a base;

[0042] Figure 6 Schematic diagram of the blank of the present invention, in which (a) is a schematic diagram of the blank formed by a single upsetting process; (b) is a schematic diagram of the blank formed by a double upsetting process. DETAILED DESCRIPTION

[0043] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] like Figure 1 As shown in the figure, for blades with special shapes, the blade body is thinner and longer with a smaller cross-sectional area, while the crown and root are thicker and shorter with a larger cross-sectional area. The resulting required blank shape is as follows: Figure 2 As shown in the figure, it is a dumbbell-shaped part with large ends and a small middle; and the height-to-diameter ratio of the blank is greater than 4, which is very easy to cause instability during the forming process. At present, direct machining or equal-diameter metal bars are generally machined into a specific shape and then forged, resulting in low material utilization and high machining costs. In addition, the isothermal forming temperature is high, mostly forming in the range of 1000-1400℃, which places more stringent requirements on mold performance. Conventional mold steel cannot be used, and expensive nickel-based high-temperature alloys and molybdenum-based alloys are mostly used, further increasing the processing cost.

[0045] In order to solve the above problems, a large aspect ratio titanium aluminum alloy billet making device is provided, comprising a bar 1, a forming die 2, a sleeve ring 3, a pressure rod 4, a base heating furnace 5 and a base 6; the bar 1 is nested in the forming die 2 after lubrication pretreatment; the forming die 2 is nested in the sleeve ring 3; the bar 1, the forming die 2 and the sleeve ring 3 form a whole, that is, an upsetting assembly, such as Figure 4 (a)

[0046] The base heating furnace 5 surrounds and connects the base 6 and the pressure rod 4, and is used to heat the base 6 and the pressure rod 4. The base 6 and the pressure rod 4 are arranged opposite to each other to form a preheating and heat preservation system. Figure 4 (b)

[0047] The upsetting assembly is placed in the base 6 for fixing and supporting the upsetting assembly; the pressure rod 4 is used to apply pressure to the upsetting assembly to complete the upsetting process.

[0048] In a specific embodiment of the present invention, the forming mold 2 is designed with at least two sets. A groove is opened at one end of the first set of forming molds 21. The shape and size of the groove are as follows: Figure 2 The second set of forming mold 22 contacts the ring 3 at one end and is provided with a groove of the same shape and size as the first set of forming mold 21, and the other end is designed according to the shape and size of the dumbbell-shaped blank; Figure 2 The shape and size of the other end of the dumbbell-shaped special-shaped blank shown are designed as required.

[0049] In a specific embodiment of the present invention, the height-to-diameter ratio of the bar material 1 is greater than 4; the pressure rod 4 is made of nickel-based high-temperature alloy or ceramic; the base 6 is made of mold steel, preferably high-quality hot-working mold steel such as H13; and the base 6 is not completely placed in the base heating furnace 5, and its external air cooling dissipates heat. There is a certain temperature gradient on the base 6 as a whole, which can support and enhance the compressive stress of the internal ring 3 and the forming mold 2; the forming mold 2 is made of high-quality ceramic mold; the ring 3 is made of a high-temperature alloy with high strength and thermal stability at 1000-1400°C, preferably nickel-based high-temperature alloys such as K403 and N403 can be used.

[0050] In a specific embodiment of the present invention, the outer diameter of the forming die 2 is 2-3 times the diameter of the bar 1; the minimum diameter of the through hole of the forming die 2 is equivalent to the diameter of the bar 1, that is, the minimum inner diameter of the second set of forming dies 22 is equal to the diameter of the bar 1.

[0051] In a specific embodiment of the present invention, the pressing rod 4 is connected to a press machine and is used to apply pressure to the bar 1 to complete the upsetting process.

[0052] In addition, the present invention also provides a method for making a titanium-aluminum alloy billet with a large aspect ratio, which is characterized by comprising the following steps:

[0053] S10. Design of blanks:

[0054] Designing a forging according to the target titanium aluminum alloy blade; the forging includes a blade root, a blade body and a blade crown; and presetting the shape and size of the blank according to the forging;

[0055] S20, obtaining a forming die 2 and raw materials: preparing a forming die 2 according to the preset shape and size of the blank in step S10, and selecting a bar material 1;

[0056] S30, using the forming die 2 to perform upsetting forming on the bar material 1 to obtain a blank;

[0057] The blank is hot worked to obtain a target titanium-aluminum alloy blade forging.

[0058] In a specific embodiment of the present invention, the target titanium aluminum alloy blade can be of any shape. Figure 1 Taking the blade with complex geometry as an example, the preset shape and size of the forging are determined.

[0059] In a specific embodiment of the present invention, S20, selecting the bar material 1 includes:

[0060] According to the shape and size of the blank in step S10, a bar 1 with a height-to-diameter ratio greater than 4 is selected as the raw material; the bar 1 includes a first end, a middle portion, and a second end;

[0061] The first end and the second end of the bar material 1 are heated, kept warm and upset respectively, while the middle portion is not deformed, so as to obtain a blank.

[0062] In a specific embodiment of the present invention, the bar material 1 needs to be lubricated before upsetting. The lubricated pretreatment is to coat the bar material 1 with a commercially available glass lubricant. The coating thickness of the glass lubricant is 1-2 mm.

[0063] In a specific embodiment of the present invention, in step S30, the bar 1 is upset and formed by the forming die 2 to obtain the blank by forging using a non-isothermal forging process, that is, the blank temperature is inconsistent with the die temperature, and the non-isothermal forging process is as follows: the temperature of the bar 1 or the blank is 1000-1400°C, the temperature of the die is 500-800°C, and the upsetting speed is 1-10 mm / s.

[0064] In a specific embodiment of the present invention, the upsetting component, the pressure rod and the base need to be heat-insulated; the heat-insulating temperature of the upsetting component is 1000-1400°C for 30-120 minutes; the heat-insulating temperature of the pressure rod and the base is 500-800°C for 1-5 hours.

[0065] In the present invention, after the insulation is completed, the base heating furnace 5 is turned off, and the insulation upsetting component is quickly transferred to the base 6 for upsetting at one end, and the forming speed is 1-10mm / s. After upsetting, the primary blank is taken out and cooled; glass lubricant is coated on the primary blank again, and placed in the second set of forming molds 22, with the undeformed end of the rod 1 facing upward, and the second set of forming molds 22 with the rod 1 placed is nested in the ring 3, and secondary insulation treatment and upsetting are performed to obtain the required blank.

[0066] The forging method of the titanium-aluminum alloy engine blade provided by the present invention is further described below in conjunction with specific embodiments.

[0067] Example 1

[0068] This example takes the titanium aluminum alloy Ti-47Al-2Cr-2Nb-0.5C as an example

[0069] S10, obtaining blanks:

[0070] Designing a forging according to the target titanium aluminum alloy blade; the forging includes a blade root, a blade body and a blade crown;

[0071] According to the preset blank shape and size of the forging;

[0072] S20, obtaining a forming mold 2 and raw materials: according to the preset shape and size of the blank in step S10, two sets of forming molds 2 are prepared, and a bar material 1 is selected;

[0073] S30, upsetting forming: the raw material is bar 1, the bar 1 is coated with glass lubricant, and placed in Figure 3 In the first forming die 21 shown in (a), the bar 1, the forming die 21 and the collar 3 are nested in sequence to form a Figure 4 The upsetting assembly shown in (a) is placed in a heating furnace and kept at 1300°C for 60 minutes; at the same time, the pressure rod 4 and the base 6 are kept at 600°C for 4 hours under the action of the base heating furnace 5. Figure 4 (b); after the insulation is completed, the base heating furnace 5 is turned off and removed, and the upsetting assembly is quickly transferred to the base 6 for upsetting at one end, with a forming speed of 1 mm / s. Figure 4 (c); after cooling, take out and obtain Figure 6(a) is a schematic diagram of a one-stage roughing forming blank, and the height-to-diameter ratio H1 / D1 of the one-stage roughing forming blank is less than 2.5; after the one-stage roughing forming blank is coated with glass lubricant, it is placed as shown in Figure 3 (b) in the second forming mold 22, and the unformed end is facing upward, and then embedded in the ring 3 to form a Figure 5 The upsetting assembly shown in (a) is placed in a heating furnace and kept at 1300°C for 60 minutes; at the same time, the pressure rod 4 and the base 6 are kept at 600°C for 4 hours under the action of the base heating furnace 5. Figure 5 (b); After the insulation is completed, the base heating furnace 5 is turned off and removed, and the upsetting assembly is quickly transferred to the base 6 for upsetting at the other end, with a forming speed of 1 mm / s. Figure 5 (c); after cooling, take out and obtain Figure 6 (b) is a schematic diagram of a two-pass upsetting forming blank, and the height-to-diameter ratio H2 / D2 of the two-pass upsetting forming blank is less than 2.5.

[0074] After the two upsetting steps are completed, a forging is obtained, and the forging is processed to obtain the target titanium-aluminum alloy blade.

[0075] Example 2

[0076] This example takes titanium aluminum alloy Ti-45Al-8Nb as an example

[0077] S10, obtaining blanks:

[0078] Designing a forging according to the target titanium aluminum alloy blade; the forging includes a blade root, a blade body and a blade crown;

[0079] According to the preset blank shape and size of the forging;

[0080] S20, obtaining a forming mold 2 and raw materials: according to the preset shape and size of the blank in step S10, two sets of forming molds 2 are prepared, and a bar material 1 is selected;

[0081] S30, upsetting: according to the preset shape and size of the forging described in step S10, prepare a blank. The raw material is a bar 1, and the bar 1 is coated with glass lubricant and placed in a Figure 3 In the first set of forming molds 21 shown in (a), the bar material 1, the first set of forming molds 21 and the collar 3 are nested in sequence to form a Figure 4 The upsetting assembly shown in (a) is placed in a heating furnace and kept at 1000°C for 120 min; at the same time, the pressure rod 4 and the base 6 are kept at 500°C for 5 h under the action of the base heating furnace 5. Figure 4(b) As shown; After the insulation is completed, the base heating furnace 5 is turned off and removed, and the upsetting component is quickly transferred to the base 6 for upsetting at one end, and the forming speed is 4mm / s. Figure 4 (c); after cooling, take out and obtain Figure 6 (a) is a schematic diagram of a one-stage roughing forming blank, and the height-to-diameter ratio H1 / D1 of the one-stage roughing forming blank is less than 2.5; after the one-stage roughing forming blank is coated with glass lubricant, it is placed as shown in Figure 3 (b) in the second set of forming mold 22, and the unformed end is facing upward, and the nested ring 3 is formed as shown in FIG. Figure 5 The upsetting assembly shown in (a) is placed in a heating furnace and kept at 1200°C for 80 minutes; at the same time, the pressure rod 4 and the base 6 are kept at 600°C for 2 hours under the action of the base heating furnace 5. Figure 5 (b) As shown; After the insulation is completed, the base heating furnace 5 is turned off and removed, and the upsetting assembly is quickly transferred to the base 6 for upsetting at the other end, and the forming speed is 4mm / s. Figure 5 (c); after cooling, take out and obtain Figure 6 (b) is a schematic diagram of a two-pass upsetting forming blank, and the height-to-diameter ratio H2 / D2 of the two-pass upsetting forming blank is less than 2.5.

[0082] After the two upsetting steps are completed, the final billet is obtained, and the billet is hot-processed to obtain the target titanium-aluminum alloy blade forging.

[0083] Example 3

[0084] This example takes the titanium aluminum alloy Ti-46Al-2Cr-2Nb-C as an example

[0085] S10, obtaining blanks:

[0086] Designing a forging according to the target titanium aluminum alloy blade; the forging includes a blade root, a blade body and a blade crown;

[0087] According to the preset blank shape and size of the forging;

[0088] S20, obtaining a forming mold 2 and raw materials: according to the preset shape and size of the blank in step S10, two sets of forming molds 2 are prepared, and a bar material 1 is selected;

[0089] S30, upsetting: according to the preset shape and size of the forging described in step S10, prepare a blank. The raw material is a bar 1, and the bar 1 is coated with glass lubricant and placed in a Figure 3 In the first set of forming molds 21 shown in (a), the bar material 1, the first set of forming molds 21 and the collar 3 are nested in sequence to form a Figure 4The upsetting assembly shown in (a) is placed in a heating furnace and kept at 1400°C for 30 minutes; at the same time, the pressure rod 4 and the base 6 are kept at 800°C for 1 hour under the action of the base heating furnace 5. Figure 4 (b) As shown; After the insulation is completed, the base heating furnace 5 is turned off and removed, and the upsetting component is quickly transferred to the base 6 for upsetting at one end, and the forming speed is 6mm / s. Figure 4 (c); after cooling, take out and obtain Figure 6 (a) is a schematic diagram of a one-stage roughing forming blank, and the height-to-diameter ratio H1 / D1 of the one-stage roughing forming blank is less than 2.5; after the one-stage roughing forming blank is coated with glass lubricant, it is placed as shown in Figure 3 (b) in the second set of forming mold 22, and the unformed end is facing upward, and the nested ring 3 is formed as shown in FIG. Figure 5 The upsetting assembly shown in (a) is placed in a heating furnace and kept at 1400°C for 30 minutes; at the same time, the pressure rod 4 and the base 6 are kept at 800°C for 1 hour under the action of the base heating furnace 5. Figure 5 (b) As shown; After the insulation is completed, the base heating furnace 5 is turned off and removed, and the upsetting assembly is quickly transferred to the base 6 for upsetting at the other end, and the forming speed is 6mm / s. Figure 5 (c); after cooling, take out and obtain Figure 6 (b) is a schematic diagram of a two-pass upsetting forming blank, and the height-to-diameter ratio H2 / D2 of the two-pass upsetting forming blank is less than 2.5.

[0090] After the two upsetting steps are completed, the final billet is obtained, and the billet is hot-processed to obtain the target titanium-aluminum alloy blade forging.

[0091] Comparative Example 1

[0092] The difference between this comparative example and Example 1 is that the bar is processed by mechanical processing. Due to the special shape of the blade, the machining of the bar that completely wraps the shape of the blade parts will result in a large machining allowance at the blade body and a very low material utilization rate.

[0093] Comparative Example 2

[0094] The difference between this comparative example and Example 1 is that: a metal bar of equal diameter is machined into a specific shape and then forged. Due to the special shape of the blade, the cross-sectional area of ​​the blade body is much smaller than the cross-sectional area of ​​the two ends of the blade. The use of equal diameter bars for machining will result in a large machining allowance at the blade body and a very low material utilization rate.

[0095] It should be noted that, although the steps of the method for upsetting a titanium-aluminum alloy with a large aspect ratio in the present disclosure are described in a specific order in the accompanying drawings, this does not require or imply that the steps must be performed in this specific order, or that all the steps shown must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps, etc.

[0096] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for making a titanium-aluminum alloy billet with a large aspect ratio, characterized in that: It comprises a bar (1), a forming die (2), a sleeve (3), a pressure rod (4), a base heating furnace (5) and a base (6); the bar (1) is nested in the forming die (2) after lubrication pretreatment; the forming die (2) is nested in the sleeve (3); the bar (1), the forming die (2) and the sleeve (3) form a whole, namely, an upsetting assembly; The base heating furnace (5) surrounds and connects the base (6) and the pressure rod (4) to heat the base (6) and the pressure rod (4), and the base (6) and the pressure rod (4) are arranged opposite to each other to form a preheating and heat preservation system; The upsetting assembly is placed in the base (6), and the base (6) is used to fix and support the upsetting assembly; the pressure rod (4) is used to apply pressure to the bar material (1) to complete the upsetting process.

2. The blank making device according to claim 1, characterized in that: The forming mold (2) is a ceramic mold; the sleeve ring (3) is made of a nickel-based alloy material; the pressure rod (4) is made of a nickel-based alloy or a ceramic material; and the base (6) is made of mold steel; The outer diameter of the forming die (2) is 2-3 times the diameter of the bar (1), and the minimum diameter of the through hole of the forming die (2) is equivalent to the diameter of the bar (1).

3. The blank making device according to claim 2, characterized in that: The upsetting component, the pressure rod (4) and the base (6) need to be subjected to heat preservation treatment; the heat preservation temperature of the upsetting component is 1000-1400°C for 30-120 minutes; the heat preservation temperature of the pressure rod (4) and the base (6) is 500-800°C for 1-5 hours.

4. A method for making a titanium-aluminum alloy billet with a large aspect ratio provided by the billet making device according to any one of claims 1 to 3, characterized in that: The following steps are involved: S10. Design of blanks: Designing a forging according to the target titanium-aluminum alloy blade; the forging includes a blade root, a blade body and a blade crown; and presetting the shape and size of the blank according to the forging; S20, obtaining a forming die (2) and raw materials: preparing a forming die (2) according to the preset shape and size of the blank in step S10, and selecting a bar material (1); S30, using the forming die (2) to perform upsetting forming on the bar material (1) to obtain a blank; The blank is hot worked to obtain a target titanium-aluminum alloy blade forging.

5. The method for making a titanium-aluminum alloy billet with a large aspect ratio according to claim 4, characterized in that: In step S20, the selecting of the bar material (1) comprises: According to the shape and size of the blank in step S10, a bar (1) with a height-to-diameter ratio greater than 4 is selected as a raw material; the bar (1) comprises a first end, a middle portion and a second end; The first end and the second end of the bar (1) are heated, kept warm and upset respectively, and the middle part is not deformed, so as to obtain a blank.

6. The method for making a titanium-aluminum alloy billet with a large aspect ratio according to claim 5, characterized in that: The bar material (1) needs to be lubricated before upsetting, and the lubricated pretreatment is to coat the bar material (1) with a glass lubricant; the coating thickness of the glass lubricant is 1-2 mm.

7. The method for making a titanium-aluminum alloy billet with a large aspect ratio according to claim 6, characterized in that: The upsetting speed is 1 to 10 mm / s.

8. The method for making a titanium-aluminum alloy billet with a large aspect ratio according to claim 4, characterized in that: In step S30, the upsetting forming adopts a non-isothermal forging forming method; the upsetting forming temperature is 1000-1400° C.; after the upsetting forming is completed, the height-to-diameter ratio H / D of the forging is less than 2.

5.

9. The method for making a titanium-aluminum alloy billet with a large aspect ratio according to claim 4, characterized in that: The target titanium aluminum alloy blade is TiAlXZ; Wherein, X is at least one of Nb, Mo, Cr, Ta, V, and Mn; Z is at least one of Fe, C, N, O, B, and Si; The atomic percentage of Al is 43%-48%, the atomic percentage of X is 0%-8%, and the atomic percentage of Z is 0%-1%.

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